New method for verification of analytical device models using transistor parameter fluctuations

In this work device parameter fluctuations are considered for verification of analytical device models. We focus on the (WL)(-1/2)-dependence of the standard deviation of the threshold voltage sigma(Vt) [1-6]. Besides the known contribution from doping variations, an explicit channel length dependence enhances substantially the (WL)(-1/2)-curve. Oxide thickness variation is shown to have minor influence on the V-T-fluctuation and the contribution of mobility fluctuation is completely negligible for a 0.5 mu m process. It has been found that a percolation model [13] for the current paths through the device can give full account of the experimentally measured values of sigma(Vt).